AMD Radeon HD 7950 Review Feat. Sapphire & XFX: Sewing Up The High-End Marketby Ryan Smith on January 31, 2012 9:02 AM EST
Announced late last month and shipping 3 weeks ago, AMD kicked off the 28nm generation with a bang with their Radeon HD 7970. Combining TSMC’s new 28nm HKMG process with AMD’s equally new Graphics Core Next Architecture, AMD finally took back the single-GPU performance crown for the first time since 2010 with an all-around impressive flagship video card.
Of course AMD has always produced multiple video cards from their high-end GPUs, and with Tahiti this was no different. The second Tahiti card has been waiting in the wings for its own launch, and that launch has finally come. Today AMD is launching the Radeon HD 7950, the cooler, quieter, and cheaper sibling of the Radeon HD 7970. Aimed right at NVIDIA’s GeForce GTX 580, AMD is looking to sew up the high-end market, and as we’ll see the Radeon HD 7950 is exactly the card to accomplish that.
|AMD GPU Specification Comparison|
|AMD Radeon HD 7970||AMD Radeon HD 7950||AMD Radeon HD 6970||AMD Radeon HD 6950|
|Memory Clock||1.375GHz (5.5GHz effective) GDDR5||1.25GHz (5GHz effective) GDDR5||1.375GHz (5.5GHz effective) GDDR5||1.25GHz (5GHz effective) GDDR5|
|Memory Bus Width||384-bit||384-bit||256-bit||256-bit|
|Manufacturing Process||TSMC 28nm||TSMC 28nm||TSMC 40nm||TSMC 40nm|
As has been the case for AMD since the 5000 series, AMD has gone with a two-pronged approach to binning and cutting down their flagship GPU for their second-tier card. The first change is an across-the-board reduction in clockspeeds, with the core clock being dropped from 925MHz to 800MHz and the memory clock being dropped from 5.5GHz to 5GHz. The second change is that the shader count has been reduced from a full 2048 SPs to 1792 SPs, accomplished by disabling 1 of the GPU’s 8 CU arrays and allowing AMD to use Tahiti GPUs with a defective CU array that would have never worked in the first place.
No other changes have been made, a particularly important consideration since it means all 32 ROPs and the 6 64bit memory channels are still in place. Altogether this gives the 7950 86% of the ROP throughput, 75% of the shader and texture throughput, and 91% of the memory bandwidth of the 7970. This should put the 7950 in direct competition with NVIDIA’s GeForce GTX 580, which typically trails the 7970 by a similar degree. Otherwise compared to the 6000 series, this makes the core performance gap between the 7950 and 7970 a bit bigger than between the 6970 and 6950, while the memory bandwidth gap is identical.
The tradeoff of course on a second-tier part is that while performance has been reduced so has power consumption. Just as with the 7970, the 7950 takes after its 6000-series predecessor, shipping with a 200W maximum board power limit. With the 7000 series AMD has not been publishing any kind of typical power numbers and thereby making the board power limit the only number they publish, but also making for a far more accurate TDP than past estimated TDP numbers as it’s an absolute limit. For gaming scenarios you’re almost always looking at less than 190W power consumption, though the spread between typical power and the PowerTune cap is not as wide on the 7950 as it was the 7970. Meanwhile for idle power consumption AMD is not providing an official number there either, but with the use of power islands the difference in idle power consumption between various core configurations has been virtually eliminated. Idle TDP should be 15W, while long idle is 3W.
In a bit of an unusual move for AMD, for the 7950 they are doing away with reference designs entirely. All 7950s will be custom to some degree—the first run will use a partner’s choice of cooler alongside a new PCB from AMD specifically for the 7950, while in the future partners will have the option of going fully custom. Furthermore partners will be shipping factory overclocked parts from right out of the gate, and at this point we’re not even sure just how many models will actually be shipping at stock clocks; neither MSI or Sapphire have a stock clocked card as part of their lineup. Overall at the low-end we’re seeing overclocked cards shipping as low as 810MHz, while 900MHz is particularly common at the high-end.
The use of customized factory overclocked cards is not unusual for AMD’s lower-end cards, but this is the first time we’ve seen AMD’s partners launch factory overclocked parts out of the gate like this, and it’s the first time we’ve seen AMD launch a part over $200 without a reference cooler. As a result the 7950 will be a true Your Mileage May Vary situation, with the gaming performance and physical performance characteristics depending heavily on how a partner has configured their card.
|Radeon HD 7950 Partner Specification Comparison|
|AMD Radeon HD 7950 (Stock)||Sapphire HD 7950 Overclock Edition||XFX R7950 Black Edition Double Dissipation|
|Memory Clock||1.25GHz (5GHz effective) GDDR5||1.25GHz (5GHz effective) GDDR5||1.375GHz (5.5GHz effective) GDDR5|
|Memory Bus Width||384-bit||384-bit||384-bit|
|Manufacturing Process||TSMC 28nm||TSMC 28nm||TSMC 28nm|
For the launch of the 7950 AMD shipped us a pair of internal reference cards built on the 7970 PCB and cooler. Since no one will actually be shipping a card like this—although they technically could if they wanted to—we also went looking for partner cards, which XFX and Sapphire provided. The XFX R7950 Black Edition Double Dissipation and Sapphire HD 7950 Overclock Edition are far more representative of what we’re actually going to see on the market; factory overclocks aside, both use open air coolers, just as with every other 7950 card we’ve seen the specs for ahead of today’s launch. Given the lack of any cards using fully exhausting blowers, it would appear that AMD and their partners have become particularly comfortable with open air coolers for 200W cards.
Last but not least of course, is pricing. AMD is continuing their conservative pricing strategy of trying to price their cards against existing competitive cards, rather than using the cost savings of the 28nm process to bring down prices across the board. As a result the 7950 is priced at $449, $100 below the 7970 and almost directly opposite the cheapest GeForce GTX 580s, making the 7950 a de facto GTX 580 competitor. This pricing strategy seems to have worked well for the 7970—cards are still selling at a brisk pace, but the shelves are rarely completely bare—and it looks like AMD is going to continue following it while they can. Meanwhile the fact that the 7950 is an entirely semi-custom lineup means that pricing is going to be equally variable, with high-end factory overclocked cards such as the Sapphire and XFX going for $479 and $499 respectively.
|Winter 2011 GPU Pricing Comparison|
|$750||GeForce GTX 590|
|Radeon HD 6990||$700|
|Radeon HD 7970||$549|
|Radeon HD 7950||$450+||GeForce GTX 580|
|Radeon HD 6970||$350||GeForce GTX 570|
|Radeon HD 6950 2GB||$250|
|$240||GeForce GTX 560 Ti|
|Radeon HD 6870||$160|
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MattM_Super - Tuesday, January 31, 2012 - linkYes I would enjoy more performance (esp at a lower power draw). I like to get ~60fps minimum @1080p. In games with fancy lighting effects, 4xAA, high res textures, like Witcher 2, metro 2033, crysis 2 dx11 current cards cant deliver that. Its a luxury sure, but one I am willing to pay for.
I also think there is still plenty of room for improvement in graphics.
sleepeeg3 - Wednesday, February 15, 2012 - linkBingo. The fanboys are too focused on bickering to realize these GPUs are blowing past 100fps on popular games. Who cares? Game companies stopped pushing the limits years ago.
chizow - Tuesday, January 31, 2012 - linkIts funny because next-gen single-GPU performance *USED* to be measured against previous gen x2 GPU card or CF/SLI where we would expect 50+% increase over last-gen single-GPU.
But yes its easy to ignore the fact the 580 also overclocks quite well. I don't know what would be worst though for a new 7950 or 7970 owner. Kepler launching and make these prices look like tragic comedy, or AMD releasing the HD89xx not too long after to make them feel even worst about their purchase.
Either way, you make a compelling argument against buying one of these cards today.
Master_shake_ - Tuesday, January 31, 2012 - linkyou are obviously a fanboy,
obviously you missed the part where the 7970 can oc to 1125 on the cvore and max out the vram clock with STOCK voltiage, and when you do so it beats BEATS the gtx 590 a current gen dual gpu card.
chizow - Tuesday, January 31, 2012 - linkWhile I value OC'ability, I don't consider OC to stock comparisons relevant because frankly, it makes no sense.
Every card can OC to some degree so an apples-to-apples comparison should be the primary comparison with overclockability secondary.
Tchamber - Wednesday, February 1, 2012 - linkRather than call you a fanboy, I would ask for an example of a high end card going against the previous gen x2 card...and bear in mind that ONCE does NOT consitute a trend. I think evolution of performance is always incremental, at least is has been since gtx200 and radeon 4000 series.
chizow - Wednesday, February 1, 2012 - link-GTX 280 was very close to as fast as 9800GX2
Filter prevented a link for this, but google computerbase GTX 280 review and look at performance rating summary.
-GTX 480/580 was faster than GTX 295
Same deal, google 480 review for that site.
-GTX 680 should be very close to GTX 590 performance
What makes this easier on the next-gen GPU flagship is the last-gen X2 parts generally have to make sacrifices in either bandwidth, functional units, or clockspeeds to stay within TDP envelopes along with imperfect multi-GPU scaling, so you generally see only 50-75% scaling over the top single-GPU of that generation.
So you can look at it two ways, either next-gen should be ~50% faster than the top last-gen GPU, or it is very close to the last-gen X2 GPU card.
I'm trying not to take any shots at AMD fans, but their reactions to these Tahiti parts in light of historical price and performance leads me to believe they either have very low standards/expectations or they just haven't been paying attention to the industry.
Galidou - Saturday, February 4, 2012 - link''they just haven't been paying attention to the industry''
Wait, if I buy a GPU now, and I want the top single gpu for multiple screens, whatever the people in the world think about what I WANT, I realize that I have more power for my money by buying a 7970 and I go with it, it turns out that because I have done that, I'm an AMD fanboy because I haven'T been paying attention to the industry?
OMG I'm such a tard, I forgot I haven'T paid attention to the industry so I should of paid more for a less performing card..... darn that's how stupid I am.....
chizow - Saturday, February 4, 2012 - linkIf you absolutely had to have a new card today, sure you'd have some reason to buy a 7970, but still not at these prices imo.
If you wanted to maximize your return on the dollar however, you'd be much better off waiting for Kepler because even if the 7970 still suits your needs better at that point, Kepler will almost assuredly force downward pressure on all Tahiti AND Fermi parts and force AMD and Nvidia to adjust prices accordingly. In the past AMD has done this when they launched a next-gen part first (See: 5850/5870 launch), but not this time.
This actually reminds me a lot of the X1950XTX launch. Great performance when it launched and price perfectly justified compared to Nvidia's last-gen G70/G71 designs like 7900GTX and 7950GT. But as soon as G80/8800GTX launched a few months later, it made that buy decision look horrible in retrospect.
So yes, while a X1950XTX today, er I mean 7970 today looks perfectly justified, it would be a mistake to ignore what the future holds and what the past has told us when making a buying decision.
Galidou - Sunday, February 5, 2012 - linkWhat about the pricing of gtx 280 at launch vs the price of 8800gt were selling? There's always an example about Ati making bad pricing decisions, but nvidia... not out of your mouth?
I'm no ATI fanboy, I'm just waiting for you to show us you see the other side of the medal...
Those GTX 280 650$ at launch while the 8800gt was about 55-65% of the performance of that card but HEY it was three times cheaper... No you haven't heard of? Oh I forgot, Nvidia makes no mistakes, it's ATI that did with the 4870 pricing it so low, but Nvidia... they make no mistake.
But hey the price of the 7970 accordingly to it'S performance is SO BAD compared to the triple price of that GTX 280 for not even double the performance over that nice 8800gt...